Baseball and softball governing bodies have imposed various bat performance limits over the years with the goal of regulating batted ball speeds. Each association generally develops various regulations to achieve a desired level of play. Some of these regulations are specifically aimed at regulating the performance of a bat, such as BBCOR, or “Bat-Ball Coefficient of Restitution.”
BBCOR can be perceived as a measure of the “trampoline effect” a bat exhibits during impact with a ball. Higher BBCOR values generally indicate that less energy will be lost during the bat-ball impact, which suggests a higher performance bat. Lower BBCOR values indicate that more energy will be lost during the impact, which suggests a lower performance bat. Some associations or regulatory bodies dictate a maximum allowable BBCOR value. Accordingly, bat designers look for ways to improve bats while meeting performance regulations, such as BBCOR.
In addition, when a ball bat strikes a ball or another object, the impact causes waves of vibration that players sense as shock. Vibration and shock in a ball bat can cause a player discomfort or injury. Accordingly, bat designers look for ways to reduce vibration and shock in a ball bat without overly reducing performance, feel, or the quality of the sound of an impact. For example, players generally do not want a ball bat to feel or sound like a “wet newspaper” during a hit.